Under-floor trough with heating element

ABSTRACT

An under-floor trough is provided for use with a raised-floor system. The under-floor trough includes an air-delivery assembly, one or more plurality of dampers, a support system, and a heating element. A control unit, removable from above the raised-floor system, and a baffle are disposed within the air-delivery assembly. The dampers include vanes that are actuated between open and closed positions according to a time modulated duty cycle to control the flow of conditioned air to a room. The support system provides a plurality of legs disposed between the bottom of the air-delivery assembly and a sub-floor. A bracket is mounted to a wall and the under-floor trough is supported thereby. The heating element is disposed within the air-delivery assembly. Conditioned air is provided to a room at high flow rates for short durations based on the duty cycle, thereby increasing the uniformity of cooling provided to the room.

BACKGROUND

There are a number of ways to heat and air condition spaces withinbuildings. In many office buildings heating and air conditioning isachieved through ducts in the ceilings of the buildings. However,because the cooling air is introduced from above, it forces some of thewarmer air in the ceiling downward, resulting in cooling inefficienciesand a reduction in ventilation effectiveness. Ceiling-based systems alsoare often expensive to install, service, or modify, since all of therequired ducting, and terminals, among other things, are located in theceilings.

Alternatively, in many office buildings heating and air conditioning isachieved through ducts and plenums in the floors of the buildings.Typical floor terminals used with raised-floor systems in the industryare placed in an air passageway in the floor. Conditioned air isprovided to the space above the floor via the terminals and iscontrolled by throttling mechanical dampers to adjust the airflow intothe space. Such a throttling process produces inefficiencies indispersing the conditioned air to the space. Often the conditioned airstays near the floor and does not disperse throughout the space, therebycreating large temperature variations from the floor to the ceiling.Further, such temperature variations decrease the effectiveness of athermostat in holding a steady temperature within the space.

SUMMARY

Embodiments of the invention are defined by the claims below, not thissummary. A high-level overview of various aspects of the invention areprovided here for that reason, to provide an overview of the disclosure,and to introduce a selection of concepts that are further describedbelow in the detailed-description section below. This summary is notintended to identify key features or essential features of the claimedsubject matter, nor is it intended to be used as an aid in isolation todetermine the scope of the claimed subject matter.

Accordingly, an under-floor trough with a heating element is providedthat is mountable in an air passageway beneath a floor. The under-floortrough is used in conjunction with a raised-floor system. Conditionedair is provided to a subspace, or air passage between the raised-floorsystem and a sub-floor. The under-floor trough selectively controls theamount of air emitted to a room above the floor. The under-floor troughincludes an air-delivery assembly, dampers, a diffuser, a supportsystem, and a heating element.

The air-delivery assembly is mounted in an opening in a raised-floorsystem such that conditioned air from beneath the raised floor passesthrough the air-delivery assembly and into a room above the raisedfloor. The dampers are coupled to the air-delivery assembly and eachpreferably includes a vane coupled to a stepper motor. The stepper motoractuates the vane between an open and a closed position therebycontrolling the flow of air through the damper. The diffuser is disposedover the air-delivery assembly to direct the flow of conditioned and/orheated air exiting the air-delivery assembly into the room.

The support system includes a bracket mounted to a vertical structureand engages a first flange depending outwardly from the air-deliveryassembly. A second flange depending outwardly from the air-deliveryassembly engages the raised-floor system thereby allowing theair-delivery assembly to hang via the first and second flanges undernormal loads. Legs are disposed between the bottom of the air-deliveryassembly and the sub-floor to support the air-delivery assembly underloading conditions. A heating element is disposed within theair-delivery assembly to provide heated air to the space above theraised-floor system when needed.

In another aspect, a method for providing conditioned air to a room froman under-floor trough in a raised-floor system is provided. Araised-floor system and an under-floor trough are provided, theunder-floor trough having an air-delivery assembly, dampers, and adiffuser. An indication is received from a thermostat that a temperatureset point is exceeded and a time modulated duty cycle is generated.Conditioned air is provided beneath the raised-floor system and thedampers are actuated to control the flow of conditioned air from beneaththe raised floor to the space above the floor based on the timemodulated duty cycle.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Illustrative embodiments of the invention are described in detail belowwith reference to the attached drawing figures, and wherein:

FIG. 1 is a perspective view of an under-floor trough in a raised floorsystem depicting cutaway segments and having vanes in a first positionin accordance with an embodiment of the invention;

FIG. 2 is a perspective view of an under-floor trough in a raised floorsystem having vanes in a second position in accordance with anembodiment of the invention;

FIG. 3 is a cross-sectional side elevation of an under-floor trough in araised floor system in accordance with an embodiment of the invention;

FIG. 4 is a partially exploded perspective view of an under-floor troughin accordance with an embodiment of the invention;

FIG. 5 is a perspective view of an under-floor trough having afluid-heated heating element in accordance with another embodiment ofthe invention;

FIG. 6 is a flow diagram depicting a method for providing conditionedair to a room from an under-floor trough in a raised-floor system inaccordance with an embodiment of the invention; and

FIG. 7 is a perspective view of an under-floor trough in accordance withyet another embodiment of the invention.

DETAILED DESCRIPTION

The subject matter of various embodiments of the invention is describedwith specificity herein to meet statutory requirements. The descriptionitself, however, is not intended to necessarily limit the scope ofclaims. Rather, the claimed subject matter might be embodied in otherways to include different components or combinations of componentssimilar to the ones described in this document, in conjunction withother present or future technologies.

Embodiments of the invention include an under-floor trough with aheating element and a method for providing conditioned air in araised-floor system. In one embodiment, an under-floor trough with aheating element for positioning in a passageway in a raised-floor systemis described. An air-delivery assembly including a pair of sidewalls, aback having a first outwardly depending flange, a bottom, a front havinga second outwardly depending flange, and a baffle is provided. Thebaffle extends between the pair of sidewalls and is coupled to the backby brackets. Dampers are coupled to the front of the air-deliveryassembly, each having a frame with a housing. The housing contains amotor and a vane coupled between the frame and the housing. The motor iscoupled with the vane to actuate the vane between a first position and asecond position to selectively vary the flow of air. A diffuser isremoveably disposed over the air-delivery assembly to direct the flow ofair exiting the air-delivery assembly. A support system provides legscoupled between the bottom of the air-delivery assembly and a sub-floorand a bracket fixedly attached to a vertical structure and engaging thefirst flange of the back of the air-delivery assembly. An electric orfluid heated heating element is disposed within the air-deliveryassembly, between the baffle and the front of the air-delivery assembly.

In another embodiment, an under-floor trough with a heating element forpositioning in a passageway in a raised-floor system is provided. Anair-delivery assembly including a first and second sidewall, a backhaving a first outwardly depending flange, a bottom, a front having asecond outwardly depending flange, a baffle, first and secondpartitions, and a control unit are described. The first and secondpartitions are coupled between the front and the back, and the controlunit is removeably disposed therebetween. The baffle extends between afirst sidewall and a first partition and is coupled to the back bybrackets. Dampers are coupled to the front of the air-delivery assembly.Each of the dampers has a frame with a housing. The housing contains amotor. A vane is coupled between the frame and the housing and the motoris coupled with the vane to actuate the vane between a first positionand a second position to selectively vary the flow of air. A diffuser isremoveably disposed over the air-delivery assembly to direct the flow ofair exiting the air-delivery assembly. A support system having legscoupled between the bottom of the air-delivery assembly and a sub-floor,and a bracket fixedly attached to a vertical structure and engaging thefirst flange of the back of the air-delivery assembly are also provided.An electric and/or fluid heated heating element is disposed between thebaffle and the front of the air-delivery assembly and is incommunication with the control unit.

In another aspect, a method for providing conditioned air to a room froman under-floor trough in a raised-floor system is described. Araised-floor system is provided. The raised-floor system providesconditioned air within a space between a sub-floor and a raised floor.An under-floor trough having an air-delivery assembly, dampers, and adiffuser is also provided. The air-delivery assembly is supported by afirst outwardly depending flange engaging a bracket mounted to a wall, asecond outwardly depending flange engaging the raised floor, and legscoupled between the air-delivery assembly and the sub-floor. The dampersare coupled to the air-delivery assembly. Each of the dampers has amotor coupled with a vane to actuate the vane between a first positionrestricting the flow of conditioned air and a second position allowingconditioned air to flow into the room, and wherein the diffuser isremoveably disposed over the air-delivery assembly to direct the flow ofair exiting the air-delivery assembly into the room. An indication isreceived from a thermostat that a temperature set point is exceeded. Atime modulated duty cycle for supplying conditioned air to a room tomaintain a temperature set point is generated. Conditioned air issupplied to the room according to the duty cycle by actuating all of thevanes of the dampers substantially simultaneously from the firstposition to the second position to allow conditioned air to flow intothe room, or from the second position to the first position to restrictthe flow of conditioned air to the room.

Referring now initially to FIGS. 1 and 4, an under-floor trough with aheating element for use with a raised floor system is designatedgenerally by the numeral 100. The under-floor trough 100 comprises anair-delivery assembly 102, and a plurality of dampers 104. All of thepieces and components of the under-floor trough 100 as shown in FIG. 1are generally formed from sheet metal, but is should be understood thatany suitable material may be used. Further, although specific joiningtechniques are described in the embodiments below, any suitable formingand joining techniques may used to construct the under-floor trough andits components.

The air-delivery assembly 102 includes a back 106, a bottom 108, a front110, and a pair of opposed sidewalls 112 coupled between the back 106and the front 110. The back 106, bottom 108, and front 110 arepreferably integrally formed from a single piece of sheet metal and thepair of sidewalls 112 preferably have an inwardly depending flange 113along two sides to allow the sidewalls 112 to be joined to the back 106and front 110 by fasteners (not shown), as illustrated in FIG. 4. Theback 106 includes an outwardly depending first flange 107 along a topedge. The front 110 includes an outwardly depending second flange 111along a top edge. A pair of partitions 114 are coupled between the front110 and the back 106 near an end of the air-delivery assembly 102. Thepair of partitions 114, along with the back 106, bottom 108, and front110 designate a location in which a control unit 116 is disposed.

The control unit 116 may include any necessary components forcontrolling a heating element, as described in greater detail below. Thecontrol unit 116 is a drop-in unit such that it may be installed and/orremoved from above the under-floor trough 100 by manually lowering thecontrol unit 116 into position between the pair of partitions 114. Oneor more receptacles may be located within the location between the pairof partitions such that when the control unit 116 is lowered intoposition an equal number of connectors on the control unit 116 engagethe receptacles. The receptacles thereby connect the control unit 116 toany desired components and power sources. Alternatively, the controlunit 116 might be lowered into position and a number of connections mademanually by attaching wires or connectors thereto.

The control unit 116 is in communication with a thermostat or a secondcontrol unit that indicates to the control unit 116 when operation ofthe associated heating element is desired. Alternatively, the controlunit might have an integrated thermostat thereby allowing the controlunit to independently determine heating needs. In another embodiment,the control unit 116 also controls the dampers 104 as described below.The control unit 116 receives commands from a thermostat or othercontrol device indicating a desired actuation of the dampers 104.

A baffle 118 is preferably disposed between one of the partitions 114and one of the sidewalls 112 and coupled to the back 106 by a pluralityof brackets 120. With additional reference to FIGS. 3 and 4, the baffle118 is shown extending from a height slightly less that that of the back104 and the front 110 of the air-delivery assembly 102 downward towardthe bottom 108. A bottom portion 125 of the baffle 118 depends generallydownward and toward the front 110 of the air-delivery assembly 102leaving a gap between the baffle 118 and the bottom 108. In anembodiment, the baffle 118 may have any desired shape and configurationto provide a desired air flow through the air-delivery assembly 102. Inanother embodiment, the baffle may have one or more notches (not shown)or cutouts along an upper edge to accommodate a diffuser 164 (describedbelow).

With reference now to FIGS. 1, 2 and 3, the dampers 104 will bediscussed. FIG. 2 shows an under-floor trough 100 having three dampers104 coupled to the front 110 of the air-delivery assembly 102. It shouldbe appreciated that the air-delivery assembly 102 may have any suitablenumber of dampers 104 without departing from the scope of the inventionas described herein. FIG. 3 depicts a cross-sectional elevation of theunder-floor trough 100. The dampers 104 include a frame 126, a pair ofhubs 128 (one of each pair is not visible), and a vane 130. The frame126 includes a top wall 132, a sidewall 134, a bottom wall 136, and ahousing 138. The top, side, and bottom walls 132, 134, and 136 of theframe 126 are integrally connected. However, it should be appreciatedthat the walls 132, 134, and 136 may be separate pieces attachedtogether by any suitable means. The top wall 132 of the frame 126contains a pair of upwardly depending flanges 140, the sidewall 134 ofthe frame 126 contains a pair of outwardly depending flanges 142, andthe bottom wall 136 of the frame 126 contains a pair of downwardlydepending flanges 144. The sidewall 134 contains a centrally locatedaperture (not shown), the purpose of which will be further discussedbelow. The housing 138 is coupled to the top and bottom walls 132 and136 of the frame 126 at a location opposite the sidewall 134 of theframe 126.

The housing 138 contains a cover (not shown) and houses a motor (notshown), having an output shaft (not shown), that protrudes from anaperture 154 located in the housing 138. The motor, while not shown, isa preferably stepper motor that uses magnetic attraction to move thevane 130 between an open or second position (FIG. 2) and a first orclosed position (FIG. 1). The aperture 146 in the sidewall 134 of theframe 126 and the aperture 154 in a sidewall 158 of the housing 138align and the pair of hubs 128 are rotatably coupled therewith.

The motor, along with the damper 104, are disclosed in U.S. patentapplication Ser. No. 10/606,085 (issued as U.S. Pat. No. 7,241,217)which is herein incorporated by reference. As discussed therein, acontrol system for the damper 104 receives input signals from athermostat or other sensor in the room. Based on the signals received,the control system provides control signals to the motor which operatesthe damper 104. The control system may provide an “open” signal or a“close” signal to the motor. When an open signal is provided, the motoris activated to rotate the vane 130 of the damper 104 to the second, oropen position, and the damper 104 remains in that position until a closesignal is provided, wherein, the motor rotates the vane 130 of thedamper 104 to the first, or closed position.

The control of the damper 104 involves assigning the damper 104 a timemodulated duty cycle having a fairly short duration, normally under twominutes and often amounting only to seconds. During each duty cycle, thedamper 104 is maintained open (or “on”) for a time period that isdependent upon a set point temperature and the actual temperature in theroom or space. During the remainder of each duty cycle, the damper 104is maintained closed (or “off”). The duration of each “open” or “on”time period is adjusted in order to maintain the set point temperature.

The vane 130 is connected with the housing 138 and the frame 126 by thepair of hubs 128. The vane 130 is a generally rectangular piece of metalthat extends between the sidewall 134 of the frame 126 and the housing138. The details of the hubs 128 are described but not shown. The hubs128 each contain a channel (not shown) that receives a portion of thevane 130. The hubs 128 also each contain an aperture (not shown). Theaperture of one hub 128 receives the output shaft of the motor while theaperture of the other hub 128 receives a rod (not shown) that isrotatably coupled with the aperture 146 of the sidewall 134. This allowsthe vane 130 to be rotated relative to the frame 126 between the firstand second positions by activation of the motor. FIG. 1 shows theunder-floor trough 100 with the vanes 130 of the dampers 104 in thefirst or closed position while FIG. 2 shows the under-floor trough 100with the vanes 130 of the dampers 104 in the second or open position.

As depicted in FIGS. 1-5 and 7, a diffuser 164 is removeably disposedover and between the back 104 and front 110 of the air-delivery assembly102 and spans between the pair of sidewalls 112. The diffuser includes aplurality of vanes 166, a back flange 168, a front flange 170, and apair of side flanges 172. The vanes 166 extend the length of theair-delivery assembly 102 and direct a flow of air from the air-deliveryassembly 102. In an embodiment, the vanes 166 are angled fifteen degreesfrom vertical and toward the front 110 in order to direct a flow of airfrom the air-delivery assembly 102 into a room at an approximatelyfifteen degree angle. It is to be understood that any desired angle maybe provided to some or all of the vanes 166 or the vanes may beadjustable without departing from the scope of the invention. The back,front, and side flanges 168, 170, and 172 are preferably integral andframe the plurality of vanes 166. Further, the back flange 168 engagesthe first flange 107 of the back 106, the front flange 170 engages thesecond flange 111 of the front 110, and the side flanges 172 engage anupper surface 173 of a raised floor system 174 to position and supportthe diffuser 164 in position over the air-deliver assembly 102. Thediffuser 164 further includes a downwardly depending flange 176 thatruns the perimeter of the plurality of vanes 166 and that is sized tofit within the back 104, front 110, and sidewalls 112 of theair-delivery system 102.

With continued reference primarily to FIGS. 3 and 4, a support systemfor the under-floor trough is described according to an embodiment ofthe invention. The support system includes a plurality of legs 178 and abracket 180. The legs 178 are disposed between the bottom 108 of theair-delivery assembly 102 and a sub-floor 182. The legs 178 include abracket 184 that engages the air-delivery assembly 102 and couplesthereto. The legs 178 also include a foot 186 that is coupled to thesub-floor 182. Additionally, the length of the legs 178 is adjustablesuch that a desired height may be provided to the under-floor trough100. It should be understood that the legs 178 may include any desiredsupport leg technology available in the art and may be coupled to theunder-floor trough 100 and the sub-floor 182 by any available method.

The support system further includes the bracket 180 mounted to a wall188 or other vertical structure. The bracket 180 comprises one or moresections of angle steel (steel bar having two parallel, adjacent, flatportions perpendicular to one another) and is fixedly attached to thewall 188 by fasteners. The bracket 180 may comprise any suitable formproduced from any suitable material. In an embodiment a glue, caulk, orother sealant is disposed between the bracket 180 and the wall 188 toprovide a greater seal against the flow of air between the bracket 180and the wall 188. The bracket 180 engages the first flange 107 of theback 106 of the air-delivery assembly 102 by providing a rigid surfaceon which the first flange 107 rests. The engagement of the bracket 180and the first flange 107 may also provide a seal against the flow of airbetween the bracket 180 and the air-delivery assembly 102. An additionalcomponent of the support system is the raised floor system 174. Theraised floor system 174 also provides a rigid upper surface 173 uponwhich the second flange 111 of the front 110 of the air-deliveryassembly 102 rests.

As such, the under-floor trough 100 is supported primarily by the firstflange 107 resting atop the bracket 180 and the second flange 111resting atop the raised-floor system 174 under normal loads (e.g. theweight of the under-floor trough 100). Under loading conditions, such aswhere a person or object exerts a downward force on the diffuser 164,the support provided by the bracket 180, the flanges 107 and 111, andthe raised-floor system 174 may not be sufficient to retain theunder-floor trough 100 within its position in the raised-floor system174. Thus, the legs 178 provide additional support to aid incounteracting such loading conditions. In another embodiment, the legs178 provide the primary support for the under-floor trough 100 undernormal loads and under loading conditions.

FIGS. 1, 3 and 4 depict an electric heating element 122 disposed betweenthe baffle 118 and the front 110 of the air-delivery assembly 102. Theelectric heating element 122 is coupled to the baffle 118 via aplurality of brackets 124, as shown in FIG. 1. The electric heatingelement 122 may alternatively be coupled to the front 110, the bottom108, or mounted between the baffle 118 and the front 110 by any otherdesirable method. The electric heating element 122 is furthercommunicatively coupled to the control unit 116 which controls the powerinput to the electric heating element 122. In an embodiment, theelectric heating element 122 is a low voltage electric heating element.In another embodiment, the control unit pulses the power input to theelectric heating element 122 to provide a more energy efficient heatingcycle.

FIG. 5 depicts an under-floor trough 200 including a heated-fluidheating element 202. The under-floor trough 200 includes an air-deliveryassembly 204, a plurality of dampers 206, and a support system similarto that described above with respect to the under-floor trough 100.Further, the under-floor trough 200 operates similarly to theunder-floor trough 100, as is described below. The air-delivery assembly204 does not include a pair of partitions and a control unit as such isnot necessary to control the heated-fluid heating element 202. Inanother embodiment, a pair of partitions and a control unit are employedto control a heated-fluid heating element.

The heated-fluid heating element 202 includes a pipe 208 and a pluralityof vanes 210 coupled around the pipe 208. The pipe 204 enters and exitsthe air-delivery assembly 204 through apertures 212 (only one of whichis visible in FIG. 5) in a front wall 214 in the air-delivery assembly204. Hot water is supplied through the pipe 208, whereby the heat fromthe water is transferred to the pipe 208 into the vanes 210 and then toair surrounding the vanes 210. It is to be understood that any suitableheated-fluid heating element may be employed in embodiments of theinvention and any suitable heated fluid may be used without departingfrom the scope of the invention as described herein.

With reference now to FIG. 6 and with additional reference to FIGS. 1-4,a method 600 for providing conditioned air to a room from an under-floortrough 100 in a raised-floor system 174 is described according to anembodiment of the invention. A raised-floor system 174 is providedhaving conditioned air within a space between the sub-floor 182 and theraised floor 174, at 602. Conditioned air is supplied beneath the raisedfloor system 174 via any suitable air conditioning or blower system. Inan embodiment, the space between the sub-floor 182 and the raised-floorsystem 174 is a plenum and the conditioned air is provided to theplenum, the dampers 104 being in fluid communication therewith. Inanother embodiment, ductwork is provided beneath the raised floor system174 and attaches to the dampers 104. At 604, an under-floor trough isprovided. As depicted in FIG. 1 the assembled under-floor trough 100 hasa plurality of dampers 104 and is positioned along a wall 188 with thediffuser 164 visible from above the raised floor system 174.Additionally, a thermostat is supplied in a room above the raised floorsystem 174 for use in controlling the heating and cooling of the room.

Initially, the vanes 130 of the dampers 104 are in a first or closedposition, as depicted by the shadowed lines of FIG. 3. An indication isreceived from a thermostat that the temperature of the space is above orbelow a temperature set point, at 606. At 608, a time modulated dutycycle for supplying heated and/or conditioned air to the room to achieveand/or maintain the temperature set point is generated. The timemodulated duty cycle utilizes a series of actuations of the vanes 166 ofthe dampers 104 between open and closed positions to pulse the flow ofconditioned air to the room. Conditioned air is supplied to the room byactuating the vanes 130 of the dampers 104 from the closed position tothe open position and back to the closed position according to the dutycycle, at 610. As such, the flow of conditioned air to the room iseither predominantly restricted or predominantly un-restricted therebyproviding flow rates at either near 0% or near 100% of a possible givenpressurization of the conditioned air within the raised-floor system174.

By actuating the vanes 130 to the open position, depicted in FIG. 3, ahigh flow rate of conditioned air is provided to the room from theunder-floor trough 100. The conditioned air flows through the dampers104 and into the air-delivery assembly 102 where it strikes the baffle118. The baffle 118 is positioned and formed so as to divert the flow ofconditioned air upward through the diffuser 164. As described above, theplurality of vanes 166 of the diffuser 164 are designed such that theflow of conditioned air is directed toward the center of the room andaway from the wall 188. Further, by providing a high flow rate ofconditioned air, the air is forced upwards into the room and mixesthroughout a larger volume of the room than if it were supplied at alesser flow rate. Additionally, such a high flow rate overcomes issueswith the flow of conditioned air out of the air-delivery unit 102 andinto the room caused by the large volume within the air-delivery unit102.

For example, under-floor trough systems of the prior art employ a methodof mechanically throttling a damper to control the flow rate of agenerally continuous input of conditioned air into a room. As such, theflow rate of conditioned air is kept at a level much less than 100% ofthe available flow and is varied between 0% and 100% by throttling thedamper. Thus, as the conditioned air exits such trough systems, it staysnear the floor and fills the room from the floor up due to the lowbuoyancy of cold air and because there is not a sufficient flow rate toeject the conditioned air into the upper elevations of the room. Issueswith such a system include large temperature variations from the floor,which is very cool, to the ceiling, which is much warmer. Additionally,in such circumstances the cold air does not easily reach the elevationof a controlling thermostat. Therefore, the thermostat continues to callfor additional cooling even though the lower elevations of the room maybe well below a temperature set point. This may lead to greatinefficiencies in the cooling of the room as well as occupants thereofbeing uncomfortable.

By employing the time modulated duty cycle and actuating the dampers 104between fully open and fully closed as described above, a much moreefficient cooling process may be achieved. Further, the high flow rateof conditioned air through the under-floor trough 100 causes theconditioned air flow to higher elevations of the room and mix moreevenly throughout the room. Additionally, by employing the timemodulated duty cycle to pulse the flow of conditioned air to the room, agenerally equal volume of conditioned air as might be used in amechanically throttled system of the prior art described above is used.Thus, a generally equal amount of conditioned air is used to provide amuch more uniformly cooled room. As such, over time, embodiments of theinvention may become increasingly more efficient over mechanicallythrottled systems of the prior art, because occupants and thermostats ofrooms cooled by the prior art systems may make inefficient adjustmentsto compensate for the uneven dispersion of conditioned air within theroom, among other reasons.

Referring again to FIG. 3, the operation of the under-floor trough 100for heating a space above a raised floor system 174 is describedaccording to an embodiment of the invention. As described previously,the under-floor trough 100 is mounted adjacent to a wall 188 via abracket 180 mounted to the wall 188. During a heating cycle the vanes130 of the dampers 104 are in a first or closed position, therebyessentially eliminating the flow of air into the air-delivery assembly102 from under the raised-floor system 174. The control unit 116receives an input from a thermostat or a second control unit requestingheat for an associated room. The control unit 116 provides anappropriate power supply to the electric heating element 122, therebycausing the electric heating element 122 to generate heat. As theelectric heating element 122 heats the air contained within theair-delivery assembly 102 between the baffle 118 and the front 110, thebuoyancy of the air increases causing the heated air to rise and flowout of the under-floor trough 100 and into the room. Such a flow of theheated air creates a draft which pulls cooler air downward and into theair-delivery assembly 102 into the space between the back 106 and thebaffle 118. The downward flow of cool air continues along the bottom 108and under the baffle 118. The air is then drawn upward between thebaffle 118 and the front 110 and around the electric heating element 122to be heated.

Additionally, the positioning of the under-floor trough 100 along a wall188 is advantageous in that the wall 188 is often an exterior wall whichmay have one or more windows. As such, the wall 188 is generally coolerthan the interior of the room and thus the air near the wall 188 iscooler. The cool air near the wall 188 readily sinks, or flows downwardinto the under-floor trough 100 due to its reduced buoyancy as comparedto the warmer air within the room. The additional air flow imparted bythe sinking cooler air along the wall 188 may further increase thecirculation of air throughout the room as the air cycles through theunder-floor trough 100, into the room and back toward the wall 188.

In an embodiment, the control unit 116 directs a heating cycle in whichthe electric heating element 122 is pulsed. Such a pulsed heating cyclemay provide increased benefits to efficiency and circulation among otherbenefits.

In another embodiment, an under-floor trough 200 includes a fluid-heatedheating element 202. The fluid-heated heating element is heated by afluid, such as for example water provide via a boiler system. Theheating of the element is controlled by a thermostat or other suitablecontrol unit. Further, the heating and airflow created therefrom aresimilar to that described above with respect to the under-floor trough100 having an electric heating element 122.

FIG. 7 illustrates an alternate embodiment of the present invention. Inthis embodiment, an under-floor trough 300 has a single damper 104coupled to a front 302 of an air-delivery assembly 304. This under-floortrough 300 uses a support system similar to that described above withrespect to the under-floor trough 100. Further, the under-floor trough300 operates similarly to the under-floor trough 100, as is describedabove.

Many different arrangements of the various components depicted, as wellas components not shown, are possible without departing from the scopeof the claims below. Embodiments of the inventive technology have beendescribed with the intent to be illustrative rather than restrictive.Alternative embodiments will become apparent to readers of thisdisclosure after and because of reading it. Alternative means ofimplementing the aforementioned can be completed without departing fromthe scope of the claims below. Certain features and subcombinations areof utility and may be employed without reference to other features andsubcombinations and are contemplated within the scope of the claims.

1. An under-floor trough with a heating element for positioning in apassageway in a raised-floor system, the under-floor trough including:an air-delivery assembly having a pair of sidewalls, a back having afirst outwardly depending flange, a bottom, a front having a secondoutwardly depending flange, and a baffle, wherein said baffle extendsbetween said pair of sidewalls and is positioned between the front andthe back; one or more dampers coupled to said air-delivery assembly,each of said one or more dampers having a frame with a housing, thehousing containing a motor, and a vane coupled between the frame and thehousing, wherein the motor is coupled with the vane to actuate the vanebetween a first position and a second position to selectively vary theflow of air into the air-delivery assembly; a diffuser removeablydisposed over said air-delivery assembly to direct the flow of airexiting the air-delivery assembly; a support system having a pluralityof legs coupled between said air-delivery assembly and a sub-floor and abracket fixedly attached to a vertical structure and engaging said firstflange of said back of said air-delivery assembly; and a heating elementdisposed between said baffle and one of said back and said front of saidair-delivery assembly.
 2. The under-floor trough of claim 1, whereinsaid motor is a stepper motor.
 3. The under-floor trough of claim 2,wherein the stepper motor selectively moves the vane from the firstposition to the second position via magnetic attraction and/orrepulsion.
 4. The under-floor trough of claim 1, wherein the under-floortrough is primarily supported under normal loads by the first flangeengaging said bracket and the second flange engaging said raised-floorsystem.
 5. The under-floor trough of claim 4, wherein the under-floortrough is primarily supported by the plurality of legs when verticalloads are applied to the under-floor trough.
 6. The under-floor troughof claim 1, wherein said bracket provides an air seal between saidair-delivery assembly and said vertical structure.
 7. The under-floortrough of claim 1, wherein said vertical structure is a wall.
 8. Theunder-floor trough of claim 9, wherein all of the vanes of the pluralityof dampers are actuated from the first position to the second positionor from the second position to the first position substantiallysimultaneously.
 9. The under-floor trough of claim 8, wherein the vanesare actuated to control the flow of conditioned air from beneath theraised-floor system and into a room above the raised-floor system basedon a time modulated duty cycle.
 10. An under-floor trough with a heatingelement for positioning in a passageway in a raised-floor system, theunder-floor trough including: an air-delivery assembly having a firstsidewall, a second sidewall, a back having a first outwardly dependingflange, a bottom, a front having a second outwardly depending flange, abaffle, a first partition, a second partition, and a control unit,wherein said baffle extends between said first sidewall and said firstpartition and is coupled to said back by a plurality of brackets,wherein said first partition and second partition is coupled betweensaid front and wherein said back, and said control unit is removeablydisposed between said first partition and second partition; a pluralityof dampers coupled to said front of said air-delivery assembly, each ofsaid dampers having a frame with a housing, the housing containing amotor, and a vane coupled between the frame and the housing, wherein themotor is coupled with the vane to actuate the vane between a firstposition and a second position to selectively vary the flow of air; adiffuser removeably disposed over said air-delivery assembly to directthe flow of air exiting the air-delivery assembly; a support systemhaving a plurality of legs coupled between said air-delivery assemblyand a sub-floor and a bracket fixedly attached to a vertical structureand engaging said first flange of said back of said air-deliveryassembly; and a heating element disposed between said baffle and saidfront of said air-delivery assembly and in communication with saidcontrol unit.
 11. The under-floor trough of claim 10, wherein saidcontrol unit is accessible from above said raised-floor system.
 12. Theunder-floor trough of claim 11, wherein said control unit comprises adrop-in unit.
 13. The under-floor trough of claim 10, wherein theunder-floor trough is primarily supported under normal loads by thefirst flange engaging said bracket of the support system and the secondflange engaging said raised-floor system.
 14. The under-floor trough ofclaim 13, wherein the under-floor trough is primarily supported by theplurality of legs when vertical loads are applied to the under-floortrough.
 15. The under-floor trough of claim 10, wherein said bracket ofthe support system provides an air seal between said air-deliveryassembly and said vertical structure.
 16. The under-floor trough ofclaim 10, wherein the heating element is an electric heating element andwherein the electric heating element is a low voltage heating element.17. The under-floor trough of claim 10, wherein the heating element isan electric heating element and wherein the electric heating element ispulsed.
 18. The under-floor trough of claim 10, wherein all of the vanesof the plurality of dampers are actuated from the first position to thesecond position or from the second position to the first positionsubstantially simultaneously.
 19. The under-floor trough of claim 18,wherein the vanes are moved to control the flow of conditioned air frombeneath the raised-floor system and into a room above the raised-floorsystem based on a time modulated duty cycle.
 20. A method for providingconditioned air to a room from an under-floor trough in a raised-floorsystem, the method comprising: providing a raised-floor system havingconditioned air within a space between a sub-floor and a raised floor;providing an under-floor trough having an air-delivery assembly, aplurality of dampers, and a diffuser, wherein said air-delivery assemblyis supported by a first outwardly depending flange engaging a bracketmounted to a wall, a second outwardly depending flange engaging saidraised floor, and a plurality of legs coupled between the air-deliveryassembly and the sub-floor, and wherein said plurality of dampers arecoupled to said air-delivery assembly, each of said dampers having amotor coupled with a vane to actuate the vane between a first positionand a second position, and wherein said diffuser is removeably disposedover said air-delivery assembly to direct the flow of air exiting theair-delivery assembly into the room; receiving an indication from athermostat that the temperature of a room exceeds a temperature setpoint; generating a time modulated duty cycle for supplying conditionedair to the room to maintain a temperature set point; and supplyingconditioned air to the room according to said duty cycle by actuatingall of said vanes of said plurality of dampers substantiallysimultaneously from said first position to said second position to allowconditioned air to flow into the room or from said second position tosaid first position to restrict the flow of conditioned air to the room.